In Paul Thomas Anderson’s “Boogie Nights,” Philip Seymour Hoffman transformed a bit part into a breakout, playing a gay boom operator who harbored a secret crush on fictitious porn star Dirk Diggler (Mark Wahlberg). A longtime Anderson collaborator, he’s also appeared in four of the director’s other movies: “Hard Eight” (1996), “Magnolia” (1999), “Punch-Drunk Love” (2002) and “The Master,” to be released on Sept. 14 by The Weinstein Co. (For more, go to Fall Season 2012: Movies). He’s won dozens of high-profile awards, including the best actor Oscar in 2006 for “Capote.”

Hoffman, 45, was the first actor to sign on to “The Master,” and communicated frequently with Anderson as he developed the script, which centers on the volatile relationship between two very different types of men. Hoffman plays Lancaster Dodd, the magnetic leader of a made-up spiritual movement called “The Cause,” which was inspired by Scientology. Dodd describes himself as a “writer, a doctor, a nuclear physicist, a theoretical philosopher,” upon meeting a traumatized World War II vet (Joaquin Phoenix) aboard a cruise ship. Phoenix’s character, by contrast, is an enigmatic drifter named Freddie who can’t hold down a job or maintain a relationship, and is prone to violence and excessive drinking. A 1950s-style attempt at an Extreme Metaphysical Makeover ensues.

So far, the movie, which premiered last week at the Venice Film Festival, has been getting overwhelmingly positive reviews (see here and here). But it will be interesting to see how the church of Scientology, which has yet to issue a statement about the film, will react to it.

Mark Headley, a former Scientologist and author of a book about the religion, read the screenplay and wrote an essay last month in The Daily Beast saying that “The Master” is “the biggest fictional middle finger ever flown their way.” Tom Cruise, the most famous Scientologist in the world, who has worked closely with Anderson—he played a charismatic guru in “Magnolia”—can be expected to have some issues with its portrayal of his religion. A spokeswoman for Mr. Cruise had no comment.

Hoffman, who agreed to a brief phone interview to promote the film, seemed perturbed by the media’s intense focus on its Scientology-oriented aspects, and was reticent to discuss anything else about the project with any degree of specificity, which was admittedly frustrating. An edited transcript:

How did you help shape the script?

We’d talk about story and the character and what he took from that was what he took. I don’t know how much I helped shape it. That would be a question for him.

Paul Thomas Anderson seems to be fascinated by these charismatic svengali types, and he has said that your character, Lancaster Dodd, was inspired by L. Ron Hubbard. Could you tell me about what types of men you were thinking about when you were reading the script and preparing for the role?

The idea that L. Ron Hubbard and that movement was the basis for some story in the film is accurate, but it’s really not a film about that, so it isn’t accurate enough for me to play L. Ron Hubbard. And so I didn’t. It wasn’t enough of that kind of story to do that. So I wanted to think about other people because it was a fictional thing and the character is a very fictional character. So, I thought about other people who had that kind of charisma and moved people and people followed them, and what that meant for me. I steered clear of anything having to do with “The L. Ron Hubbard Story” because it’s too specific and the film wasn’t going to support that, so I thought it would be confusing.

Which people did you think about who had that kind of charisma? I saw you have mentioned that Orson Welles was an inspiration.

People really want to talk about that but I didn’t try to play Orson Welles either. There’s nothing to look at here. It’s like when you are thinking about something, a lot of ideas go through your head, and references go through your head but ultimately you are just looking for something in yourself. There are certain behaviors, the way people sound. I didn’t really try to play anybody if that’s what you’re looking for.

No, I’m not looking for that, just some idea of the types of people who may have collectively influenced your performance—obviously the charismatic-but-flawed character is an archetype in cinema, ranging from “Citizen Kane” to the “Godfather.”

I had a unique view of the guy that he was a down-to-earth guy. You know what I mean? So it was like how do you get a guy like that to be so successful? Gathering people, moving people getting people to follow him—it’s a unique kind of thing. So it’s a lot of different things.

You just finished playing Willy Loman on Broadway. Both “Death of a Salesman” and “The Master” tackle this theme of post-war alienation, but from different angles. Did you take anything away from one that you brought with you to the other?

No.

Does it bother you that everyone’s been calling this “the Scientology movie”?

No, not so much. Though I do have to answer the question a lot.

What do you think about it?

What I just said.

Do you think that once people see the movie they will still think it’s about Scientology?

But you do see the similarities though, right? “Auditing” versus “Processing”—the techniques to rid people of traumatic life experiences—the disdain of non-believers, the likeness to Scientology’s Sea Org, the fact that it takes place in 1950, the year “Dianetics” came out, etc.

Sure. If people are going to be that literal about it then they are. But it’s not something to be taken literally or my character would be called L. Ron Hubbard. People do this all the time. Films are like that all the time. They are inspired by things but they are not those things. Every season there are films like that. But because it’s around that thing people are paying attention to it.

So, do you think people are paying more attention to it because Scientology has been in the news so much lately with the Tom Cruise-Katie Holmes divorce?

It’s because you guys are paying attention to it. To be honest it’s because of you guys. If I did interviews and it didn’t come up then it wouldn’t come up. But it comes up because there’s an appetite for it, from you guys. It’s a good story.

What would you prefer that people focused on?

It doesn’t matter to me what people focus on. You asked me where I think it comes from and I think it comes from the appetite to have a titillating story. And I think that comes out of mentioning Scientology. Instead of them being like “Was this based on it?” and me saying “Yeah, it was but it’s not about that” and [them] saying “OK let’s move on,” you know, that never happens. They want to keep—you want to keep—asking more questions because you want to make it more than that, but it isn’t more than that.

Well, the movie wasn’t really so much about this religion as it is about the clash of two men—one who has been rendered almost feral and the other who has deluded others (and possibly himself) into believing that he is in control of his emotions. Do you think your character is aware that he’s sort of this gifted improviser, or does he believe in his abilities?

I think he thought he was doing something that was helping people. And that’s why he was successful. What eventually becomes of him is alluded to at the end of the movie. I don’t think he’s fraudulent. You see him do what he does, and it’s actually effective. You see its effects on Joaquin’s character. But I never saw him as a fraudulent guy, no.

So he’s fully earnest when he talks about past lives in France, time travel, curing leukemia, etc.

He was very earnest. He believes in himself. That’s what is ultimately so dangerous about a guy like that. You have to have more self-doubt than that, a little healthy “I’m not sure of what I’m doing.”

I like the title of Lancaster Dodd’s second book, “The Split Saber,” and how it’s presented as “a gift to homo sapiens,” which is an insanely egomaniacal thing to say. Was that inspired by any of these actual New Age books?

That’s a Paul question. I don’t know. The titles of the books are weird.

Did you read any New Age self-help books when you were preparing for the role?

There was no reason to. Why? Just because of a title? I had to think about the kind of thing the guy did with people because it’s in the script. But I didn’t have to think about self-help books because they had nothing to do with the movie.

The reason I was asking was because I thought it might be something that would be helpful for an actor to get in the head of these types of spiritual gurus, how they speak, how they think.

No, no. I didn’t take it literally. It would be a cynical way to research a guy like that by getting in the head of people who make goofy self-help books.

Was there a lot of improvising on set?

Not so much.

Joaquin Phoenix seemed completely wild. Did you know what he was going to do?

You always try to keep it fresh. The character is wild. So yeah, he had to be that way, not so much Joaquin but the character.

Was it unusual to be around somebody who is that unhinged?

No. I mean, a lot of people are unhinged. I’ve worked with a lot of characters that are unhinged. I’ve played characters that are unhinged. That’s, like, my job.

Is there anything else you wanted to add about the film?

No.

[Correction: Earlier versions of this post left out the fact that Hoffman appeared in "Hard Eight."]

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